First-Principles Investigations of the Electronic Structure and Mechanical Characteristics of Nd3+-Doped YAlO3 Crystals

Abstract

Near-infrared laser radiation based on Nd³⁺-doped yttrium ortho-aluminate (Nd:YAlO₃, Nd:YAP) has garnered significant interest regarding solid-state lasers. Nevertheless, the crystal microstructures and electronic characteristics of Nd:YAP are still unclear, and the unique physical properties underlying its enormous applications require clarification. In this study, we conducted first-principles calculations at the atomic level to explore the electronic properties and mechanical characteristics of both pure YAP and Nd³⁺-doped YAP. The results suggest that the substitution of the Y³⁺ ion site with the Nd³⁺ impurity ion induces slight structural distortion in the YAP crystal lattice. An impurity band emerges between the original conduction band and the valence band, attributed to the 4f orbital of the Nd³⁺ ion, exerting a substantial influence on the narrowing of the band gap. Through an analysis of the mechanical characteristics of both pure YAP and Nd:YAP, we conclude that the incorporation of Nd³⁺ atoms leads to a reduction in the mechanical properties of YAP to a certain extent. Our study can serve as a foundational data source for investigations into material performance, especially for the application of Nd:YAP in solid-state laser systems.